Artificial nipples are classified into thump type nipples and roman or round type nipples. In such artificial nipples (hereinafter, simply refer to as “nipples”), there is no change in the positions of feeding holes that are located at the centers of the nipples while there is a difference only in the sizes of the feeding holes according to infants' ages.
In case of a thumb type nipple, since a feeding hole 2 is merely located at a position offset slightly upward from the center of the nipple as shown in FIG. 1, the feeding hole 2 is considered as being substantially directed to the palate of an infant when the infant normally holds a teat portion 1 of the nipple in the mouth.
Since the feeding hole is not oriented directly toward the throat of the infant in view of the position of the feeding hole 2, this configuration may be understood as being a safe configuration for avoiding the throat. However, it should be noted that it is not true due to the following reasons.
That is, although the feeding hole 2 in case of the thumb type nipple is located approximately in the middle of the palate of the infant, this position can never be considered as a safe position in unspecified postures such as a lying posture except normal postures such as a sitting or standing posture of the infant when the infant sucks milk. When the infant lies on his/her back, it can be considered that his/her airway is opened. Even though the feeding hole 2 is oriented toward the palate of the infant, it is substantially impossible for the infant himself/herself to delay or block a linear flow of milk introduced from the palate into the throat of the infant in view of low reflexes of the infant. Therefore, a configuration in which the feeding hole 2 is in line with the throat as in the thumb type nipple can be considered as having low safety.
In case of a roman type nipple, the aforementioned problem becomes much severer. In this type nipple, a feeding hole 2 is formed at the vertex of a sphere-type teat portion 1 as shown in FIG. 2 and thus a direction in which milk is discharged from the feeding hole 2 is in line with the direction of the throat of the infant. Accordingly, since the milk is introduced directly into the throat when the infant sucks the milk, there is a very high possibility that a risk of respiratory disturbance may occur.
In cases of both the thumb and roman type nipples, air is not commonly introduced into the mouth of the infant. Thus, a high vacuum pressure is established in the mouth when the infant sucks the milk, and a high milk suction pressure is generated. This leads introduction of the sucked milk into ears, eyes or lungs of the infant, which may be a cause of various diseases and death. Therefore, there is a need for a countermeasure against such a problem.
Further, in such a conventional nipple, there is a high possibility that an indented neck portion 3 of the nipple with which teeth of the infant intensively come into contact may be damaged, as compared with the other portions of the nipple. Thus, there is the risk of safety accident due to tear of the nipple.
In this regards, the present applicant has proposed a silicon nipple with a fiber net embedded therein in Korean Utility Model Registration No. 137262. With the embedded fiber net 4 in the nipple as shown in FIG. 3, even though a portion of the nipple is torn, the torn silicon portion of the nipple is prevented from falling off.
Although the nipple with the fiber net embedded therein can be easily manufactured since the fiber net 4 is embedded throughout the nipple, however, a great deal of the fiber net is required, which leads in economic inefficiency and increase of the unit cost of the nipple.